Model systems using invertebrates have provided insightful and innovative new information towards elucidating more complex neural events in mammals. Dr. Nagle is using the control of egg- laying behavior in the marine mollusc Aplysia to understand the cellular and molecular bases of neuroendocrine function. The neurosecretory bag cells that synthesize and release a novel neuropeptide egg-laying hormone (ELH) are model neuroendocrine cells that have been used extensively to elucidate how neural cells function. His research program is aimed at isolating and characterizing a membrane receptor protein which, in the intact animal, binds the ELH and initiates a complex series of cellular and behavioral events that culminate in egg laying and reproductive functions. The gene that encodes this behaviorally important receptor protein will be cloned and sequenced. With this knowledge, functional questions about how a hormonal signal may be transduced by neural and non-neural cells can be examined. Thus, understanding the expression of the peptide receptor in this simple behavioral system should enhance our understanding and lead to generalities about receptor expression in neuroendocrine functions.
